The invention relates to a low friction gliding plate designed to optimize the process of packing one or more compressible objects, such as insulation material. A conventional machine for packing one or more compressible objects into one larger packet usually uses a technique where the object(s) are gathered, compressed and subsequently directed into the wrapping foil forming one stack. In this way the wrapping foil is fitted tightly around the three sides of the packet. At the fourth end, the object(s) are being held in a compressed state by a set of spears. The wrapping foil is wrapped around the spears and sealed e.g. by welding where after the spears are removed. The latter will cause the compressed object(s) to expand so as to fill out the empty space left by the spears.
In the industry of insulation material it is of outmost importance that the cubic content of the packets is reduced to a minimum, enabling transportation of an increased number of packets per volume. By using the spears described, the volume of the packets is greater than desired, but can be compensated for by over-compressing the compressible objects. Hence, when the spears are removed, the compressed object(s) will expand into the space made by the over-compression. However, by using over-compression there is a risk that the material properties of the objects are damaged.
An additional problem with using spears is the friction forces existing between both the spears and the wrapping foil and the spears and the compressed objects. When the spears are removed both the wrapping foil and the compressed object(s) can be damaged due to the friction forces.
Further, it is quite common for the wrapping foil to have some kind of text or illustration printed onto it. Part of this print can be transferred to the spears when the spears and the wrapping foil slide against one another thereby inducing friction between the spears and the wrapping foil. If the individual objects have been pre-packed in a printed foil, part of this print will also be transferred to the spears, inducing additional friction again. Over time, there will thus be a continuous increase of friction between the spears and the foil and/or the objects. The problem with friction induced damages on foil and/or the compressed object(s) will merely grow as the print from the foil is transferred and accumulated on the spears. The only way to solve this problem is to clean the spears on a regular basis. However, this is time consuming and increases the down time of the packaging machine.
The conventional wrapping machine therefore leaves the problem of either damaging the product due to over-compression or wasting wrapping foil due to rewinding of the foil. In addition, there is the problem of friction induced damage to the product/wrapping foil. A device is needed, which would have minimum friction force towards the foil and/or the compressible object(s) and render over-compression of the compressible object(s) and rewinding of the wrapping foil superfluous.